| 摘要 |
PROBLEM TO BE SOLVED: To provide a copper resistance compensating circuit for a coil in which a temperature dependence characteristic of a coil for detection is surely compensated and operation characteristics of a high frequency oscillation type proximity sensor, for example, are stabilized. SOLUTION: The copper resistance compensating circuit is provided with an oscillation driving circuit for applying a driving voltage to one end of a two-yarn coil 1 which is substantially composed of two coil conductors commonly connecting and twisting one end together for using one of the coil conductors as a coil for a resonance circuit and using the other coil conductor as a coil for copper resistance compensation, and a compensation means for virtually short-circuiting the copper resistance component of the coil for the resonance circuit by making a current of the equal level with a current flowing from one end of the coil for the resonance circuit to the other end flow from the other end of the coil for the resonance circuit to the other end of the coil for copper resistance compensation. COPYRIGHT: (C)2004,JPO
|
